2-adamantyl-and 2,6-diadamantyl-p-cresols

ABSTRACT

NEW ADAMANTANE SUBSTITUTED CRESOLS HAVING THE STRUCTURES:   2-(3-R2,7-R1-ADAMANT-1-YL),4-CH3-PHENOL, AND 2,6-DI-   (3-R2,7-R1-ADAMANT-1-YL),4-CH3-PHENOL   WHEREIN R1 AND R2 ARE HYDROGEN OR HYDROCARBYL RADICALS CONTAINING FROM 1 TO 10 CARBON ATOMS SELECTED FROM THE GROUP OF ALKYL, CYCLOALKYL AND ARYL. THE NOVEL COMPOSITIONS OF MATTER ARE USEFUL AS POLYMER STABILIZERS WHICH INHIBIT THE DECOMPOSITION OF HYDROCARBON POLYMERS LIKE POLYETHYLENE, POLYPROPYLENE, POLYBUTENES, STYRENEBUTADIENE COPOLYMERS, POLY(4 METHYL PENTENE) AND THE LIKE.

United States Patent New adamantane substituted cresols having the structures: a

wherein R and R are hydrogen or hydrocarbyl radicals containing from 1 to carbon atoms selected from the group. of alkyl, cycloalkyl and aryl. The novel compositions of matter are useful as polymer stabilizers which inhibit the decomposition of hydrocarbon polymers like polyethylene, polypropylene, polybutenes, styrenebutadiene copolymers, poly(4 methyl'p'entene) and the like.

-BACKGROUND on THE INVENTION ..,F 1 P 1 Y The invention relates to novel adamantane substituted cresols and to the process of making same.

(2) Description of the prior art The carbonnucleus of adamantane compounds contains 'tencarbon atoms arranged in a symmetrical (strainless) manner sucli'ltha'tl'there are ;-three condensed sixmembcred rings and four bridgehead carbon atoms. The structure of adama'ntane is typically depicted as follows:

SUMMARY OF THE INVENTION It has now been found that adamantane substituted cresols having the structures:

where R and R are hydrogen or hydrocarbyl radicals containing from 1 to 10 carbon atoms selected from the group of alkyl, cycloalkyl and can be successfully prepared by an alkylation type reaction of the cresol with the corresponding halogen substituted adamantane com- 3,781,371 Patented Dec. 25, 1973 pound with a hydrated ferric chloride catalyst at an alkylating temperature in the range of to C. The compositions of the present invention are useful as polymer stabilizers which inhibit the decomposition of hydrocarbon polymers.

DESCRIPTION OF THE PREFERRED EMBODIMENTS H0 C B3 on; 9 H01.

c11 ca;

The reaction will produce alkylation at the 2-position of the p-cresol if a large excess of p-cresol is employed, e.g. at a molar ratio of p-cresol to halo-adamantane of 3:1 to 10:1. Conversely, di-alkylation of the p-cresol in the 2 and 6 positions:

occurs when a large excess of halo-adamantane is employed, tag. at a molar ratio of 3:1 to 10:1.

As is apparent from'the foregoing equation, the R and R substituents on the adamantane nucleus are unaffected and remain in place during the reaction.

The preferred halogen substituted adamantane starting material for the present process is a bridgehead bromoor chloro adamantane having 1030 carbon atoms, 0 to 3 bridgehead hydrocarbon radicals and 0-6 nonbridgehead hydrocarbon radicals, each having 1-10 carbon atoms, selected from the group consisting of alkyl, cycloalkyl and aryl. These radicals can contain branched chains, however, tertiary hydrocarbon atoms are not desirable in the hydrocarbon substituent since they would compete in the alkylation reaction and contribute to a more complex product. Thus adamantanes having 0-2 bridgehead hydrocarbon radicals selected from the group consisting of straight chain alkyl and phenyl are pre ferred.

Particularly preferredstarting materials are the bridgehead bromoor chloro-derivatives of adamantane, dimethyl adamantane and diethyladamantane.

The halogen substituted adamantane and alkyladamantane starting materials are known and disclosed in the following references: Smith and Williams, Journal of Organic Chemistry, 26, 2207 (1961); Stetter and Wulif, Chem. Ber., 93, 1366 (1960); Stetter, Anguw, Chem. International Edition, vol. 1 (1962); German Pat. 1,101,- 410; US. Pat. 3,096,372; US. Pat. 3,577,468; and US. Pat. 3,666,806.

The phenolic compounds useful in this invention are monoand di-adducts of p-cresol and dimethyladamantane as well as monoand di-adducts of p-cresol and adamantane.

The following examples illustrate the invention:

EMMPLE I 24.3 grams (0.1 gr. mol) of 1-bromo-3,5-dimethyladamantane are admixed with 54.1 grams (0.5 gr. mol) of para-cresol in the presence of 0.005 gram of The mixture is maintained at 130 to 170 C. for 10 to 60 minutes or until HBr evolution ceases, with agitation and inert (N gas purge. The reaction mixture is treated with 20% NaOH solution to remove residual catalyst, HBr and unreacted p-cresol. The main reaction product, 1-(3-methyl 6 hydroxyphenyl) 3,5 dimethyladamantane, is purified by fractional vacuum distillation of the neutralized, dried reaction product.

EXAMPLE 11 145.9 grams (0.6 gr. mol) of 1-bromo-3,5-dimethyladamantane are mixed with 10.8 grams (0.1 gr. mol) of para-cresol in the presence of 0.01 gram FeCl -12H O. The mixture is heated to 140160 C. with agitation and an inert gas purge, and maintained at that temperature for 10-60 minutes or until evolution of HBr ceases. After cooling, the reaction mixture is washed with water to remove residual catalyst and HBr, then dried. The main reaction product, 4-methyl-2,6-di-(3,5-dimethyladamantyl) phenol, may be isolated from unreacted starting material and by-products by fractional distillation under high vacuum.

The adamantane substituted phenolic compounds of this invention have particular utility as stabilizing agents for the thermal and/or oxidative decomposition of many hydrocarbon polymers.

The invention claimed is:

1. As a new composition of matter, compounds having the structure:

wherein R and R are hydrogen or hydrocarbyl radicals containing from 1 to carbon atoms selected from the group consisting of alkyl, cycloalkyl and aryl and A is selected from the group consisting of hydrogen and the structure:

2. As a new composition of matter, compounds having the structure:

HO CH 4 wherein R and R are hydrogen or hydrocarbyl radicals containing from 1 to 10 carbon atoms selected from the group consisting of alkyl, cycloalkyl and aryl.

3. A compound according to claim 2 wherein R is hydrogen and R is selected from the group consisting of alkyl, cycloalkyl and aryl.

4. A compound according to claim 2 wherein R and R are selected from the group consisting of alkyl, cycloalkyl and aryl.

5. A compound according to claim 2 wherein R and R are selected from the group consisting of methyl and ethyl.

6. A compound according to claim 2 wherein R and R are methyl.

7. As a new composition of matter, compounds having the structure:

R2 CH3 wherein R and R are hydrogen or hydrocarbyl radicals containing 1 to 10 carbon atoms selected from the group consisting of alkyl, cycloalkyl and aryl.

8. A compound according to claim 7 wherein R is hydrogen and R is selected from the group consisting of alkyl, cycloalkyl and aryl.

9. A compound according to claim 7 wherein R and R are selected fiom the group consisting of alkyl, cycloalkyl and aryl.

10. A compound according to claim 7 wherein R and R are selected from the group consisting of methyl and ethyl.

11. A compound according to claim 7 wherein R and Udding et al.: Tetrahedron Letters, No. 11, pp. 1345- 50, 1968.

LEON ZITVER, Primary Examiner N. MORGENSTERN, Assistant Examiner US. Cl. X.R. 

